Optical articles comprising a polyimide are disclosed herein.
Fiber optic technology has been traditionally used for long distance communication but with increases in internet usage for large amounts of data transfer, much of the bandwidth in the existing optical network is used for this data communication and at higher rates. Increasingly fiber optics is being used to connect computer networks to meet the huge demand of data and at higher data transfer speeds, even at shorter distances.
Optical connectors or transceivers are components of optical networks, which are used to connect servers, where in the transceivers function to convert light into electrical signals and electrical signals back into light signals. The optics in these devices, termed as optical sub assemblies (OSA) is currently made out of a polyetherimide, which acts as lens and optics housing assembly. These transceivers are pluggable and stand alone components.
It is increasingly desirable to move from pluggable transceivers to an on board transceivers system and to use optical waveguides or light pipes on a backplane to connect boards and waveguides on printed circuit boards as busses to increase the data transfer rates. These applications require high glass transition temperature polymers.
These devices require injection molded polymer micro lenses and waveguides, since that fabrication process is well suited for manufacturing at high volumes and low cost. The lenses are required to retain their shape at temperatures in excess of 240° C., since laser transmitter/transceiver modules are exposed to high temperatures during their placement on printed circuit boards by a solder re-flow process or a solder bath, especially lead free solder processes. For this reason, only polymers with high glass transition temperatures can be used. In addition, as these lens or waveguides perform the function of light path between laser diodes, photo detectors and fiber optics, these polymers have to be clean, transparent with high transmission, specifically in the range of 600 nm to 1600 nanometers (nm), which are typical communication wavelength used in optical communication and be able to retain the optical characteristics and be dimensionally stable after exposure to humidity.
Hence there exists an unmet need for optical articles comprising a polymer with high transmission in the range of 600 nm to 1600 nm, dimensional stability even after exposure to humidity and capable of withstanding lead free solder processes.